Downlink mobile reference signal transmission and RRM measurement method and device

Abstract

Aspects of the present invention provide a downlink mobile reference signal transmission method. The method may include transmitting a mobile reference signal including a first mobile reference signal and an additional mobile reference signal, wherein the first mobile reference signal includes a first mobile reference signal burst, wherein each of the first mobile reference signal bursts is multiplexed with a synchronization signal block, the additional mobile reference signal includes a second mobile reference signal burst, and the additional mobile reference signal is configured to be transmitted or not transmitted. By utilizing the present invention, downlink mobile reference signal transmission and radio resource management measurement can be better performed.

Description

[0001] This case is a divisional application of application number 201880002483.5. The original application date is January 9, 2018. The name of the invention is "Downlink mobile reference signal transmission and RRM measurement method and user equipment".

[0002] Cross-references

[0003] This application claims priority to U.S. Provisional Application No. 62 / 443,846, filed on January 9, 2017, entitled “Transmission of Mobility Reference Signal (MRS) for DL ​​RRM measurement,” and the entirety of the above application is incorporated by reference into this application. Technical Field

[0004] The present invention relates to wireless communications, and more particularly to a downlink (DL) reference signal (RS) for radio resource management (RRM) measurements. Background Art

[0005] The background technology section provided here is to generally present the context of the present invention. The work described in this background technology section and the aspects described in this section did not constitute prior art at the time of application, and the work of these currently named inventors is neither explicitly nor implicitly admitted to be prior art of the present invention.

[0006] In Long Term Evolution (LTE) networks, a Common Reference Signal (CRS) can be transmitted in each subframe over the full carrier bandwidth. RRM measurements can be performed based on CRS. However, in the New Radio (NR) air interface, the always-on wideband CRS is removed in order to reduce RS overhead, inter-cell interference, and user equipment (UE) power consumption. A new RS design can be introduced in NR systems for RRM measurements. Summary of the invention

[0007] Aspects of the present invention provide a downlink mobile reference signal transmission method. The method may include transmitting a mobile reference signal including a first mobile reference signal and an additional mobile reference signal, wherein the first mobile reference signal includes one or more first mobile reference signal bursts, wherein each of the one or more first mobile reference signal bursts is multiplexed with a synchronization signal block, the additional mobile reference signal includes one or more second mobile reference signal bursts, and the additional mobile reference signal is configured to be transmitted or not transmitted.

[0008] In one embodiment, the method may further include transmitting a first or second mobile reference signal burst including a plurality of mobile reference signal symbols on a series of beams during beam scanning. The mobile reference signal sequence transmitted on a beam is generated based on a beam index of the beam.

[0009] In one example, the burst length of the one or more first or second mobile reference signal bursts is configurable. In one embodiment, the method may also include transmitting a mobile reference signal configuration corresponding to a serving cell or a neighboring cell of a user equipment, wherein the mobile reference signal configuration includes one or more of the following configuration parameters, and the configuration parameters define the one or more second mobile reference signal bursts transmitted from the corresponding cell of the user equipment: a transmission period, a time offset relative to a synchronization signal block, a transmission bandwidth, a burst duration, and a frequency domain position. In one example, the transmission period is determined according to the speed of the user equipment.

[0010] In one example, the mobile reference signal sequence is generated based on one or more of a cell identifier, a transmission reception point identifier, or a transmission beam index of a serving cell transmitting the mobile reference signal. In one example, the frequency domain location of the one or more first or second mobile reference signal bursts depends on the cell identifier, the transmission reception point identifier, or the transmission beam index of the serving cell transmitting the mobile reference signal. In one example, the one or more first or second mobile reference signal bursts are transmitted in a subframe or time slot of a serving cell, and a neighboring cell of the serving cell does not have uplink transmission.

[0011] Aspects of the present invention provide a radio resource control connection mode radio resource management measurement method. The method may include receiving, by a user equipment, a mobile reference signal configuration corresponding to a service cell and a neighboring cell of the user equipment; receiving, according to the mobile reference signal configuration, a mobile reference signal transmitted from the service cell and the neighboring cell of the user equipment, wherein each of the mobile reference signals includes a first part mobile reference signal and an additional part mobile reference signal, the first part mobile reference signal includes one or more first mobile reference signal bursts, wherein each of the one or more first mobile reference signal bursts is multiplexed with a synchronization signal block, the additional part mobile reference signal includes one or more second mobile reference signal bursts, and the additional part mobile reference signal is configured to be transmitted or not transmitted; and generating a radio resource management measurement result based on the received mobile reference signal.

[0012] In one embodiment, the method may also include, based on the received mobile reference signal, performing one or more of the following functions: demodulation of a physical broadcast channel in a synchronization signal block multiplexed with the one or more first mobile reference signal bursts, time and / or frequency synchronization tracking, or channel characteristic estimation.

[0013] In one embodiment, the method may also include receiving the one or more first or second mobile reference signal bursts including multiple mobile reference signal symbols from a series of beams, wherein the series of beams are transmitted from the serving cell or one of the neighboring cells during a beam scanning process.

[0014] An aspect of the present invention provides a radio resource control idle mode radio resource management measurement method. The method may include receiving, by a user equipment, a mobile reference signal transmitted from a serving cell and a neighboring cell of the user equipment, wherein each of the mobile reference signals includes one or more first mobile reference signal bursts, wherein each of the one or more first mobile reference signal bursts is multiplexed with a synchronization signal block, wherein each of the mobile reference signals is generated based on a cell identifier, a transmission reception point identifier and / or a beam index of each cell corresponding to the mobile reference signal; and generating a radio resource management measurement result based on the received mobile reference signal.

[0015] By utilizing the present invention, downlink mobile reference signal transmission and radio resource management measurements can be better performed. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Various exemplary embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein like numerals represent like elements, wherein:

[0017] Figure 1A wireless communication network according to various embodiments of the invention is shown.

[0018] Figure 2 An exemplary Mobile Reference Signal (MRS) configuration according to an embodiment of the present invention is shown.

[0019] Figure 3 Another exemplary MRS configuration according to an embodiment of the present invention is shown.

[0020] Figure 4 An exemplary synchronization signal block (SSB) multiplexed with a first MRS burst in a synchronization signal (SS) region according to an embodiment of the present invention is shown.

[0021] Figure 5 An exemplary second MRS burst according to an embodiment of the present invention is shown.

[0022] Fig. 6A An exemplary first MRS burst multiplexed with a SS burst according to an embodiment of the present invention is shown.

[0023] Figure 6B An exemplary second MRS burst according to an embodiment of the present invention is shown.

[0024] Figure 7 An exemplary Radio Resource Control (RRC) connected mode RRM measurement and reporting process according to an embodiment of the present invention is shown.

[0025] Figure 8 An exemplary RRC idle mode RRM measurement process according to an embodiment of the present invention is shown.

[0026] Fig. 9 Exemplary apparatus according to some embodiments of the invention are shown. DETAILED DESCRIPTION

[0027] Figure 1A wireless communication network 100 according to various embodiments of the present invention is shown. The network 100 may include a plurality of base stations (BS) 111-113 and a UE 161. Each BS 111-113 corresponds to a cell 121-123. For example, each BS 111-113 may control a transmission and reception point (TRP) to transmit a wireless signal to cover each cell 121-123. In one example, the network 100 complies with the fifth generation (5G) NR communication standard developed by the 3rd Generation Partnership Project (3GPP). Accordingly, each BS 111-113 may be an implementation of a gNB defined by the 3GPP NR air interface standard. The UE 161 may be a mobile phone, a laptop computer, a vehicle-mounted device, etc. The UE 161 may communicate with each BS 111-113 according to the 3GPP NR air interface standard. In other examples, the network 100 may operate according to other wireless communication standards.

[0028] In one example, UE 161 operates in RRC connected mode and performs RRM measurement and reporting procedures to facilitate handover operations. For example, UE 161 is connected to BS 111, and data or signal radio bearers can be established between UE 161 and BS 111. Therefore, cell 121 is a serving cell of UE 161. When operating in connected mode, UE 161 can monitor the signal quality of serving cell 121, for example, by calculating the reference signal received power (RSRP) of the RS received from serving cell 121. When RSRP is below a threshold (for example, due to the movement of UE 161), UE 161 can report to BS 111. In response, BS 111 can send a connected mode RRM measurement configuration to UE 161 and control UE 161 to perform RRM measurement and reporting procedures.

[0029] In particular, the connected mode RRM measurement configuration may include the MRS configuration 141 of the serving cell 121 and the neighboring cells of the UE 161. For example, the BS 111 may coordinate with the BSs 112-113 to determine the MRS configuration for each of the neighboring cells 122-123 and the serving cell 121, and then provide the MRS configuration 141 to the UE 161. For example, the BS 111 may communicate with the BSs 112-113 via interfaces 131-132, wherein the interfaces 131-132 are similar to the X2 interfaces defined in the LTE standard.

[0030] Based on the connected mode RRM measurement configuration and the MRS configuration 141, the UE 161 may perform an RRM measurement process. In the RRM measurement process, the signal quality of the cell may be measured by calculating some measurement quantities (such as RSRP measurement results) based on the RS received from the cell. In an example, the MRS configuration 141 may define a set of MRS configuration parameters of MRSs 151-153 transmitted from the serving cell 121 and the neighboring cells 122-123. For example, the MRS configuration parameters of the MRSs 151-153 may include timing information, measurement bandwidth, and location information of each resource element (RE), so that the UE 161 may capture the MRS transmission occasion accordingly. For example, UE 161 may perform inter-frequency or intra-frequency measurements accordingly and generate RSRP measurement results and / or reference signal received quality (RSRQ) measurement results for serving cell 121 and neighboring cell 122. Subsequently, when certain conditions are met (e.g., as defined in the connection mode RRM measurement configuration, the serving cell signal quality is below the neighboring cell signal quality for a certain period of time), UE 161 may report the RRM measurement results to BS 111. Based on the RRM measurement results received from UE 161, BS 111 may determine to trigger a handover process to switch UE 161 to a neighboring cell.

[0031] In another example, UE 161 operates in RRC idle mode and performs RRM measurement and reporting procedures to facilitate cell reselection operations. For example, UE 161 camps on BS 111 and cell 121 operates as a serving cell. UE 161 may receive an idle mode RRM measurement configuration from BS 111. For example, the idle mode RRM measurement configuration may be included in system information broadcast from BS 111 and received by UE 161. Similar to the connected mode, the idle mode RRM measurement configuration may include an MRS configuration 141, wherein the MRS configuration 141 defines configuration parameters of MRS 151-153 transmitted from serving cell 121 and neighboring cells 122-123.

[0032] UE 161 may monitor the signal quality of serving cell 121 while camping on BS 111. For example, when the signal quality of serving cell 121 is below a threshold value defined by an idle mode RRM measurement configuration (due to the movement of UE 161), an RRM measurement process may be triggered. UE 161 may perform RRM measurements based on the idle mode RRM measurement configuration and MRS configuration 141. For example, UE 161 may perform inter-frequency or intra-frequency measurements based on MRS 151-153 received from serving cell 121 and neighboring cells 122-123, and generate RSRP measurement results and / or RSRQ measurement results for serving cell 121 and neighboring cells 122-123. Based on the above RRM measurement results, UE 161 may determine to switch from the current serving cell 121 to another neighboring cell when a specific condition (as defined in the idle mode RRM measurement configuration) is met.

[0033] In one embodiment, the MRS transmitted from cells 121-123 may include a first part and an additional part. The first part of the MRS may be a signal that is always on and may include one or more first RS bursts. Each first RS burst may be multiplexed with an SSB during transmission. SSB refers to an RE area in an orthogonal frequency division multiplexing (OFDM) time-frequency resource grid and includes a synchronization signal (such as a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) in an LTE or NR system) and a physical broadcast channel (PBCH) carrying a master information block (MIB). SSB may be broadcast periodically from the BS and may be used by the UE during the initial access process to obtain DL synchronization and MIB system information.

[0034] The additional part MRS may include one or more second RS bursts. In particular, the transmission of the additional part MRS may be adaptively configured to facilitate RRM measurements, for example, according to the speed of UE 161. For example, when UE 161 moves at a low speed, the additional part MRS may not be transmitted. Therefore, the periodicity of the MRS may be determined by the transmission of the first MRS burst. Conversely, when UE 161 moves at a high speed, the additional part MRS may be transmitted to increase the periodicity of the MRS. Therefore, the performance of the switching operation of the high mobility UE may be improved.

[0035] Therefore, for the above-mentioned connection mode RRM measurement process, MRS 151-153 can be configured to include both the first RS burst and the additional burst. For example, when UE 161 reports to BS 111 that the signal quality is below a threshold, BS 111 can adaptively configure MRS 151-153 by coordinating with neighboring cells 122-123, such as according to the speed configuration of UE 161. For example, UE 161 can report the speed together with the signal quality when reporting to BS 111. BS 111 can generate MRS configuration 141 and send MRS configuration 141 to UE 161 in a signal, wherein MRS configuration 141 defines configuration parameters of the first part MRS and the additional part MRS.

[0036] In contrast, for the idle mode RRM measurement process described above, the idle mode RRM measurement process may be performed based on the first part of the MRS received from the serving cell 121 and the neighboring cells 122-123 (without configuring the additional part of the MRS). When a UE operating in idle mode moves across a cell boundary, the cell reselection decision may be determined by the UE itself, and the nearby BSs may not be aware of the movement of the UE. Therefore, the configuration of the additional part of the MRS may not be performed.

[0037] Figure 2 An exemplary MRS configuration 200 is shown according to an embodiment of the present invention. Figure 2 OFDM time-frequency resource region 230 is shown. Region 230 may correspond to Figure 1 DL wireless signal transmitted by BS 111-113 in the example. Region 230 may include multiple subcarriers corresponding to carrier bandwidth 221 in the frequency domain, and multiple subframes in the time domain. In one example, according to the carrier parameter set (numerology) configuration of BS 111-113, each subframe may include 1, 2, 3 or 4 time slots, and each time slot may include 7 or 14 OFDM symbols. The parameter set of the carrier frequency may be defined by the subcarrier spacing used by the carrier frequency. For example, different parameter sets may have subcarrier spacings such as 15KHz, 30KHz and 60KHz. Corresponding to different parameter sets, different subframe structures may be defined.

[0038] As shown, a series of SS zones 211-214 are contained in zone 230 and are located at the center subcarrier of carrier bandwidth 221. An SS zone may be defined as a rectangular region of REs containing one or more first MRS bursts multiplexed with one or more SSBs. An SS zone may have a transmission bandwidth 224 in the frequency domain equal to the bandwidth of the contained SSBs, and a time length 223 in the time domain, which may be equal to the number of consecutive time slots, each of which contains an SSB or an MRS burst.

[0039] MRS configuration 200 defines an MRS including a first portion of MRSs including a series of first MRS bursts 201-204. Each of the first MRS bursts 201-204 in MRS configuration 200 is included in one of SS regions 211-214, so each burst is multiplexed with one or more SSBs in each SS region 211-214.

[0040] Each SS region 211-214 may include one SSB or a series of SSBs. The series of SSBs may be referred to as an SS burst. The SSB or SS burst may be broadcast periodically. Figure 2 In the example of , the period 222 of SSB or SS burst transmission is 40 ms. Since each first MRS burst 201 - 204 is multiplexed with an SSB or SS burst, the transmission period of the first MRS burst 201 - 204 is also 40 ms.

[0041] Figure 3 FIG. 3 shows another exemplary MRS configuration 300 according to an embodiment of the present invention. The MRS configuration 300 defines an MRS including a first part and an additional part. Specifically, the first part MRS includes Figure 2 In the example, the first MRS bursts 201-204 in a series of SS regions 211-214, the additional portion MRS includes a series of second MRS bursts 301-304, wherein the second MRS bursts 301-304 are inserted between two first MRS bursts. In an example, each burst in the second bursts 301-304 has the same structure as the first bursts 201-204. As shown in the figure, the MRS configured by the MRS configuration 300 has a transmission period 322 (20ms) of Figure 2 Half of the transmission period (40 ms) of the first MRS burst 201-204 in the example.

[0042] In other examples, more than one second MRS burst may be added between two first MRS bursts so that different MRS transmission periods may be obtained. Figure 2For example, when 3 or 7 second MRS bursts are inserted between two first MRS bursts, an MRS transmission period of 10 ms or 5 ms can be obtained.

[0043] In some examples, the MRSs comprising the first MRS burst and the second MRS burst may be unevenly distributed in the time domain. Accordingly, other parameters other than the MRS transmission period may be used to define the transmission timing of the second MRS burst. For example, a time offset relative to the preceding first MRS burst may be defined for a second MRS burst following the preceding first MRS. Of course, for evenly distributed first and second MRS bursts, the time offset relative to the first MRS burst may also be used as a parameter to define the timing of a subsequent second MRS burst.

[0044] Although in Figure 3 In the example, it is assumed that the second MRS burst 301-304 has a structure similar to the first MRS burst 201-204, but in other examples, the first and second MRS bursts may have different structures. For example, the first and second MRS bursts of the same MRS may have different transmission bandwidths, different burst lengths (the time interval of the first or second MRS burst is called the burst length or burst duration) and different frequency domain positions of the MRS REs in the MRS burst.

[0045] Figure 4 An exemplary SSB 410 multiplexed with the first MRS burst 420 in the SS region 401 according to an embodiment of the present invention is shown. The SSB 410 may have a duration of 7 OFDM symbols in the time domain and a bandwidth of 24 physical resource blocks (PRBs) in the frequency domain. The SSB 410 may carry PSS 411, SSS 412, and MIB 413 in each RE. The first MRS burst 420 is carried in REs belonging to three symbols 431-433, wherein the three symbols 431-433 are in a time slot 430 containing 14 symbols. The symbol of the RE carrying the MRS is called an MRS symbol. As shown in the figure, a portion of the first MRS burst (in MRS symbols 432 and 433) is included in the SSB 410. Accordingly, the portion of the first MRS burst 420 may be used as a demodulation reference signal (DMRS) for demodulating the PBCH (including the MIB 413) during the initial access process.

[0046] A scalable parameter set with subcarrier spacing scaling may be used in NR systems. Accordingly, the SSB 410 may occupy different transmission bandwidths in the frequency domain and have different durations in the time domain, depending on the parameter set configuration of the carrier carrying the SSB 410. For example, for a parameter set configuration of 15 KHz or 60 KHz subcarrier spacing, the bandwidth of the SSB 410 occupying 24 PRBs may be 5 MHz or 20 MHz, respectively, and the duration of the SSB 410 lasting 7 symbols may be 0.5 ms or 0.125 ms, respectively.

[0047] Similarly, for different parameter set configurations, the SS region 401 having a time length of 14 symbols in the time domain and having the same bandwidth as the SSB 410 may occupy different bandwidths and last for different times. In addition, for different parameter set configurations, the bandwidth of the first MRS burst 420 (in terms of the number of PRBs, equal to Figure 4 The bandwidth of SSB 410 in the example may also vary.

[0048] In various examples, the first MRS burst 420 may have different configurations. Figure 4 In the example, the first MRS burst 420 occupies three symbols, and a portion of the MRS burst 420 (MRS symbol 431) is located outside the SSB 410. In other examples, the symbol carrying the first MRS burst can be included in the SSB 410. Accordingly, depending on the MRS configuration, the first MRS burst can have different burst lengths. For example, the burst length of the first MRS burst can be greater than the duration of the SSB or SS burst multiplexed with the MRS burst.

[0049] Note that in various examples, the SSB may have different structures. In one example, the SSB is configured to last for 4 symbols in the time domain and has the format of PSS-PBCH-SSS-PBCH, where PSS and SSS are carried in the first and third symbols and PBCH is carried in the second and fourth symbols. In the frequency domain, the SSB may have the same Figure 4 An example is a bandwidth of 24 PRBs.

[0050] Figure 5 An exemplary second MRS burst 520 according to an embodiment of the present invention is shown. The second MRS 520 may correspond to Figure 4In the example, the first MRS burst 420 may be configured to be transmitted together with the first MRS burst 420 to form an MRS. As shown, the second MRS 520 may have the same bandwidth as the first burst 420 in terms of the number of PRBs and may be distributed over 4 MRS symbols in the time domain. In other examples, as part of the same MRS that includes the first MRS burst 420 and the second MRS burst 520, the second MRS burst 520 may be configured to have the same bandwidth as the first MRS burst 420. Figure 5 Examples of different burst lengths and bandwidths For example, to improve the accuracy of RRM measurements, the second MRS burst 520 may be configured with a wider transmission bandwidth (eg, wider than 24 PRBs) and a longer burst length (eg, 1 ms or 2 ms).

[0051] During the RRM measurement process, the UE may receive multiple MRSs from a serving cell and multiple neighboring cells. Multiple MRSs may be transmitted from multiple TRPs on the same carrier frequency. In addition, multiple TRPs may adopt beamforming technology, and accordingly, the first or second MRS burst may include RS sequences transmitted from different transmission beams of the TRP. Accordingly, in one example, in order to reduce interference between multiple MRSs received from multiple neighboring cells and a serving cell, the MRS frequency position is configured to depend on a cell identification (ID), a TRP ID and / or a transmission beam index. For example, for MRS transmissions from different TRPs and different transmission beams, the RE mapping pattern for mapping each MRS sequence to REs in a time-frequency grid may be shifted in the frequency domain by the frequency of several subcarriers based on the corresponding cell ID, TRP ID and / or transmission beam index.

[0052] In another example, in order to identify MRS transmissions from different cells, TRPs or transmission beams, an MRS sequence may be generated based on a cell ID, a TRP ID and / or a beam index. For example, for an MRS configured for a specific cell, a specific TRP and a specific transmission beam, the initial value for generating each MRS sequence may depend on each cell ID, TRP ID and / or transmission beam index.

[0053] In some examples, the positions of the first and second MRS bursts in the time domain are configured to be in the DL portion of a subframe or time slot that is only DL (DLOnly) or mainly DL (DL major). In a subframe or time slot of a subframe or time slot type that is mainly DL, the DL portion can occupy a longer portion of the subframe or time slot than the uplink (Uplink, UL) portion.

[0054] In one example, the MRS burst may be configured to be located in a subframe or time slot where a neighboring cell may not have UL transmission. In this way, inter-cell DL and UL collisions due to dynamic time division multiplexing (TDD) may be avoided for DL ​​transmission of MRS bursts.

[0055] Fig. 6A An exemplary first MRS burst 630 multiplexed with a SS burst 620 according to an embodiment of the present invention is shown. The first MRS burst 630 includes a series of MRSs 631-634 transmitted in a series of time slots 611-614, respectively. The burst length of the first MRS burst 630 may be approximately equal to 4 time slots. The SS burst 620 includes a series of SSBs 621-624 transmitted in a series of time slots 611-614, respectively. Similarly, the burst length of the SS burst 620 may last for approximately 4 time slots. Although each pair of SSBs and MRSs in one time slot 611-614 is represented by two separate rectangles, as shown in FIG. Figure 4 As shown in the example, the MRS and the RE of each SSB can be mixed together.

[0056] A series of time slots 611-614 may be transmitted on a series of transmission beams 641-644 from the TRP. For example, the TRP may continuously transmit different beams 641-644 in different directions to cover the cell (this operation may be referred to as a transmission beam sweep). In addition, the transmission of the SS burst 620 and the MRS burst 630 may be repeated at a period (e.g., 40 ms). Accordingly, in the RRM measurement process, the UE may receive a first MRS burst 630 transmitted on a series of transmission beams 641-644 from the TRP. In order for the UE to distinguish the MRS 631-634 received from a series of transmission beams, each of the MRSs 631-634 of the first MRS burst 630 may be generated based on the beam index of the transmission beams 641-644, respectively. For example, each beam index of one of the transmission beams 641-644 may be used to generate an initial value for generating the MRS 631-634. Therefore, each MRS 631-634 may be beam specific. A beam index may be configured to the UE, and the UE may accordingly distinguish different transmit beams 641-644 based on the MRS 631-634, for example, using a correlation-based scheme when generating RRM measurement results.

[0057] In one example, the UE may also use beamforming technology to receive the first MRS burst 630 and the SS burst 620. For example, each MRS 631-634 may include multiple MRS symbols, wherein each MRS symbol carries an MRS sequence. During the transmission process of time slots 611-614, the UE may continuously generate a series of receive beams (referred to as receive beam scanning) in different directions, and each receive beam may correspond to an MRS symbol in terms of transmission or reception time. By performing such a beam training process, the optimal receive beam of the UE may be determined for receiving from each TRP. In addition, in the RRM measurement process, the RRM measurement results (such as RSRP, RSRQ, etc.) of different receive beams may be calculated to better estimate the signal quality of neighboring cells.

[0058] Figure 6B An exemplary second MRS burst 660 according to an embodiment of the present invention is shown. The second MRS burst 660 may be configured to follow Fig. 6A The first MRS burst 630 in the example is transmitted to form an MRS. Fig. 6A Similarly, the second MRS burst 660 may include a series of MRSs 661-664 transmitted in a series of time slots 651-654. Each MRS 661-664 or time slot 651-654 may be transmitted on one of a series of transmit beams 671-674. Similarly, the MRSs 661-664 may be transmit beam specific so that the UE may distinguish between different transmit beams based on the MRSs 661-664 when determining signal quality.

[0059] Figure 7 An exemplary RRC connected mode RRM measurement and reporting process 700 according to an embodiment of the present invention is shown. In process 700, UE 701, serving BS 702 and a set of neighboring BSs 703 communicate with each other and perform the steps of process 700. UE 701 operates in RRC connected mode and is associated with serving BS 702. In addition, UE 701 may be located within the coverage of neighboring BS 703. UE 701 may be in a mobile state and process 700 may be performed to determine a suitable neighboring BS (other than serving BS 702) for UE 701 to associate with. The process may start at S710.

[0060] S710, UE 701 reports signal quality degradation to serving BS 702. For example, serving BS 702 may transmit an MRS, wherein the MRS includes a first MRS burst. The first MRS burst may be multiplexed with an SSB and transmitted periodically. UE 701 may receive the above-mentioned first MRS burst to monitor the signal quality of serving BS 702. For example, an RSRP measurement result may be generated based on the received MRS. Due to mobility, UE 701 may detect signal degradation of MRS. When the signal quality of MRS is lower than a threshold for a preconfigured time, UE 701 may be triggered to report to serving cell BS 702.

[0061] At S712, the serving BS 702 coordinates with the neighboring BS 703 to determine a set of MRS configurations for the serving BS 702 and the neighboring BSs. In one example, each BS 702 or 703 may control multiple TRPs to form multiple cells. The serving BS 702 may be configured with a neighboring cell list, wherein the neighboring cells are associated with the neighboring BS 703. Accordingly, the serving BS 702 may be aware of the cells of the neighboring UE 701.

[0062] In one example, due to the coordination process, the MRS configuration for each cell in the neighboring cell of UE 701 and the serving cell of UE 701 may be determined. For example, the MRS configuration of the neighboring cell may define the following configuration parameters: timing of MRS bursts (such as transmission period, time offset relative to SSB, etc.), transmission bandwidth, burst length of MRS bursts, etc. In addition, the MRS configuration of the neighboring cell may include cell-related information (such as cell ID, TRP ID, transmission beam index, etc.), wherein the cell-related information is collected from the neighboring BS 703 or pre-configured to the serving BS 702.

[0063] In some examples, the serving BS 702 may determine some MRS configuration parameters based on the moving speed of the UE 701. For example, when the UE 701 is in low mobility, the second MRS burst may not be configured to the UE 701. When the UE 701 is in high mobility, a second MRS burst with a suitable transmission period may be configured. In addition, the burst length and transmission bandwidth of the first and / or second MRS burst may also be adjusted based on the speed of the UE 701.

[0064] At S714, the serving BS 702 may transmit an RRM measurement configuration to the UE 701 to trigger the UE 701 to perform an RRM measurement process. For example, the transmission of the RRM measurement configuration may be performed through RRC signaling. The RRM measurement configuration may include an MRS configuration for each cell in the neighboring cell and the serving cell of the UE 701. Alternatively, the MRS configuration may be transmitted separately from the RRM measurement configuration. For example, the MRS configuration may be transmitted through RRC signaling, broadcast or multicast system information, or a combination of RRC signaling and system information.

[0065] In addition, the RRM measurement configuration may include other specifications that may be determined based on the MRS configuration, such as a measurement object including a to-be-measured list and its operating frequencies, a reporting configuration, a measurement identifier, filtering to be used for the RRM measurement, and a measurement gap for inter-frequency measurements.

[0066] At S716, serving BS 702 transmits MRS through the serving cell of UE 701 according to the MRS configuration of the serving cell. At S718, neighboring BS 703 transmits MRS through each neighboring cell of UE 701 according to each MRS configuration of each neighboring cell. At S716 and S718, beamforming and scalable parameter sets may be used in some neighboring cells or serving cells.

[0067] At S720, according to the RRM configuration and MRS configuration of the neighboring cells and the serving cell of the UE 701, the UE 701 performs an RRM measurement process. The RRM measurement may be performed by performing intra-frequency measurement on cells operating on the frequency of the serving cell and inter-frequency measurement on cells operating on a frequency different from the serving cell. The RRM measurement results generated based on the MRS received from the serving BS 702 and the neighboring BS 703 may include RSRP, RSRQ, and other measurement qualities.

[0068] For example, in intra-frequency measurement, UE 701 can capture the MRS burst transmission occasion at an appropriate time based on the MRS timing information. For inter-frequency measurement, the measurement gap configured by the serving BS 702 can be used to determine the measurement timing. Based on the cell ID, TRP ID and / or transmission beam index corresponding to the MRS burst, the frequency position of the MRS can be determined. Based on the transmission bandwidth and burst length of the MRS burst, the RE carrying the MRS can be appropriately located. Based on the transmission beam index, the RRM measurement results can be associated with each transmission beam.

[0069] At S722, the obtained RRM measurement results may be reported to the serving BS 702. According to the RRM configuration, the report may be triggered by an event or performed periodically.

[0070] At S724, a handover decision may be determined by the serving BS 702 based on the reported RRM measurement results. Subsequently, a handover process may be triggered and executed. The process 700 ends after S724.

[0071] Figure 8 An exemplary RRC idle mode RRM measurement process 800 according to an embodiment of the present invention is shown. In process 800, UE 801 performs RRM measurements based on MRSs received from neighboring BS 803 and BS 802 where UE 801 camps. Therefore, BS 802 can be referred to as camped BS 802. UE 801 operates in RRC idle mode and can be located within the coverage of neighboring BS 803. UE 801 can be in a mobile state, and process 800 can be performed to allow UE 801 to reselect a BS to camp on. Specifically, RRM measurements can be performed by UE 801 based on the first MRS burst included in the received MRS. The first MRS burst can be multiplexed with the SSB in each time slot carrying the SSB. Process 800 can start from S810.

[0072] At S810, UE 801 may receive RRM measurement configuration from camping BS 802. For example, the RRM measurement configuration may be included in system information periodically broadcasted from camping BS 802.

[0073] The RRM measurement configuration may include the MRS configuration of the serving cell and the neighboring cells of UE 801. For example, the camping BS 802 may control the operation of the serving cell of UE 801, and each neighboring BS 803 may control a plurality of TRPs corresponding to the neighboring cells of UE 801. In one example, the MRS configuration may include a neighboring cell list, and the operating frequency and parameter set configuration of the neighboring cells.

[0074] In addition, in one example, the MRS configuration of the neighboring cell may include timing information (including period) of the first MRS burst (or equivalent SSB or SS burst), burst length of each first MRS burst, frequency domain position (RE position), etc. In one example, the transmission bandwidth of the SSB of each neighboring cell or serving cell may be standardized for the number of PRBs. The transmission bandwidth of the first MRS burst may be determined based on the bandwidth of each SSB.

[0075] Moreover, the MRS configuration may include a cell ID, a TRP ID, and / or a transmit beam index for each neighboring cell. In some examples, an MRS sequence for a cell may be generated based on the cell ID, TRP ID, and / or transmit beam index of the cell. Therefore, based on the MRS configuration, RRM measurement results for MRS sequences corresponding to different cells, different TRPs, or different transmit beams may be distinguished, for example, based on a correlation-based scheme. Knowledge of the signal quality of different transmit beams may be used to implement beam management (such as beam tracking or beam switching) for beamforming transmissions of a serving cell or a neighboring cell.

[0076] In addition to the MRS configuration, the RRM measurement configuration may contain other parameters for conducting the RRM measurement process or cell reselection. In other examples, the MRS configuration may be transmitted separately from the transmission of the RRM measurement configuration.

[0077] At S812, an MRS may be transmitted from the resident BS 802 and received at the UE 801. At S814, an MRS may be transmitted from the neighboring BS 803 and received at the UE 801. In some examples, for the UE 801 in idle mode, only the first MRS burst multiplexed with the SSB is used for RRM measurements for the purpose of cell reselection. Note, however, that there may be a second MRS burst transmitted from a cell associated with the resident BS 802 or the neighboring BS 803, wherein the second MRS burst is used by other UEs operating in RRC connected mode and performing RRM measurements.

[0078] At S816, UE 801 may perform RRM measurement based on the RRM measurement configuration and MRS configuration received at S810. For example, based on the captured MRS burst, RRM measurement results (such as RSRP, RSRQ, etc.) of different cells, different TRPs and / or different transmission beams may be generated.

[0079] At S818, UE 801 may make a decision based on the RRM measurement result obtained at S816 to reselect a neighboring cell to camp on. For example, when the signal quality of the serving cell is lower than the signal quality of the neighboring cell and the quality difference is greater than a threshold for a preconfigured time, a cell reselection process may be triggered. Process 800 may end after S818.

[0080] Although the MRS comprising the first and second MRS bursts described in the present invention can be used for DL ​​RRM measurements, in various examples, the MRS can also be used for other purposes. In one example, since the MRS (or a portion of the MRS) can be mapped to the RE in the symbol carrying the PBCH, the MRS can be used for channel estimation in the RRC connection mode or the RRC idle mode, and the result of the channel estimation can be used for coherent demodulation of the PBCH in the RRC connection mode or the RRC idle mode. In one example, the MRS described in the present invention can be used to estimate channel properties, such as Doppler spread or delay spread, in the RRC connection mode and the RRC idle mode. The result of the channel property estimation can be used for adaptive signal reception. For example, frequency synchronization can be performed to compensate for the Doppler spread, or channel equalization can be performed to compensate for the delay spread.

[0081] In one example, the MRS described in the present invention can be used to track time and / or frequency synchronization in RRC connected mode and RRC idle mode. Since an MRS burst can contain RS sequences in multiple symbols, the performance of time and frequency tracking can be improved compared to RS carried in one symbol within the transmission opportunity. For applications of channel characteristic estimation and time / frequency synchronization tracking, the MRS described in the present invention can be adaptively configured with various transmission periods for different channel conditions, where different channel conditions can change with different speeds.

[0082] Fig. 9 900 according to some embodiments of the present invention. The device 900 may be used to implement various embodiments of the present invention. The device 900 may include a processor 910, a memory 920, and a radio frequency (RF) module 930. Fig. 9 As shown, the above components are coupled together. In some examples, device 900 can be used to implement the BS described in the present invention. Accordingly, processor 910 can be configured to perform various functions or processes performed by the BS described in the present invention. In other examples, device 900 can be used to implement the UE described in the present invention. Accordingly, processor 910 can be configured to perform various functions or processes performed by the UE described in the present invention.

[0083] The processor 910 may be implemented in hardware, software, or a combination thereof. In some examples, the processor 910 may be implemented using an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), or the like containing a circuit, wherein the circuit may be configured to perform the various functions described in the present invention. In one example, the memory 920 may store program instructions, wherein the program instructions cause the processor 910 to perform various functions. The memory 920 may include a read-only memory (ROM), a random access memory (RAM), a flash memory, a hard disk drive, or the like.

[0084] The RF module 930 may receive a digital signal from the processor 910 and transmit the signal to a receiver via the antenna 940; or receive a wireless signal from a transmitter and accordingly generate a digital signal provided to the processor 910. The RF module 930 may include a digital to analog converter (DAC) / analog to digital converter (ADC), a frequency down converter / up converter, a filter, and an amplifier for receiving and transmitting operations. If the device 900 is used to implement a BS, the antenna 940 may include one or more TRPs, each of which includes one or more antenna elements.

[0085] The device 900 may selectively include other components, such as input and output devices, additional central processing units (CPUs) or signal processing circuits, etc. Accordingly, the device 900 may perform other additional functions, such as executing applications and processing other communication protocols.

[0086] Although aspects of the present invention have been described in conjunction with specific exemplary embodiments, these examples may be substituted, modified, and altered. Therefore, the embodiments described herein are intended to be illustrative, not restrictive. Changes may be made without departing from the scope of the claims of the present invention.

Claims

1. A method for transmitting a downlink mobile reference signal, comprising: transmitting a mobile reference signal comprising a first partial mobile reference signal and an additional partial mobile reference signal, wherein the first part of the mobile reference signal comprises one or more first mobile reference signal bursts, wherein each of the one or more first mobile reference signal bursts is multiplexed with a synchronization signal block, and The additional mobile reference signal portion includes one or more second mobile reference signal bursts, and the additional mobile reference signal portion is configured to be transmitted or not transmitted, Wherein, when the additional portion of the mobile reference signal is configured to be transmitted, the transmission bandwidth of the one or more second mobile reference signal bursts is equal to or greater than the transmission bandwidth of the synchronization signal block.

2. The method for transmitting a downlink mobile reference signal according to claim 1, wherein: Also includes: During beam scanning, a first or second mobile reference signal burst including a plurality of mobile reference signal symbols is transmitted on a series of beams.

3. The method for transmitting a downlink mobile reference signal according to claim 2, wherein: A mobile reference signal sequence transmitted on a beam is generated based on a beam index of the beam, such that the mobile reference signal sequence indicates the beam index of the beam.

4. The method for transmitting a downlink mobile reference signal according to claim 1, wherein: The burst length of the one or more first or second mobile reference signal bursts may be configurable.

5. The method for transmitting a downlink mobile reference signal according to claim 1, wherein: Also includes: Transmitting a mobile reference signal configuration corresponding to a serving cell or a neighboring cell of a user equipment, wherein the mobile reference signal configuration comprises one or more of the following configuration parameters, the configuration parameters defining the one or more second mobile reference signal bursts transmitted from the corresponding cell to the user equipment: Transmission cycle, The time offset relative to the synchronization signal block, Transmission bandwidth, The duration of the burst, and Frequency domain position.

6. The method for transmitting a downlink mobile reference signal according to claim 1, wherein: Also includes: The transmission period of the mobile reference signal is determined according to the speed of the user equipment.

7. The method for transmitting a downlink mobile reference signal according to claim 1, wherein: A mobile reference signal sequence is generated based on one or more of a cell identifier of a serving cell transmitting the mobile reference signal, a transmission reception point identifier, or a transmission beam index.

8. The method for transmitting a downlink mobile reference signal according to claim 1, wherein: The frequency domain positions of the one or more first or second mobile reference signal bursts depend on a cell identifier, a transmission reception point identifier or a transmission beam index of a serving cell transmitting the mobile reference signal.

9. The method for transmitting a downlink mobile reference signal according to claim 1, wherein: The one or more first or second mobile reference signal bursts are not transmitted in a subframe or time slot of a serving cell, wherein a neighboring cell of the serving cell has uplink transmission.

10. A radio resource management measurement method, comprising: Receiving, by a user equipment, a mobile reference signal configuration corresponding to a serving cell and a neighboring cell of the user equipment; receiving a mobile reference signal transmitted from the serving cell and the neighboring cell of the user equipment according to the mobile reference signal configuration, Each of the mobile reference signals comprises a first mobile reference signal and an additional mobile reference signal, the first mobile reference signal comprises one or more first mobile reference signal bursts, wherein each of the one or more first mobile reference signal bursts is multiplexed with a synchronization signal block, the additional mobile reference signal comprises one or more second mobile reference signal bursts, and the additional mobile reference signal is configured to be transmitted or not transmitted; as well as generating a radio resource management measurement result based on the received mobile reference signal, Wherein, when the additional portion of the mobile reference signal is configured to be transmitted, the transmission bandwidth of the one or more second mobile reference signal bursts is equal to or greater than the transmission bandwidth of the synchronization signal block.

11. The radio resource management measurement method according to claim 10, characterized in that: One of the mobile reference signal configurations comprises one or more of the following configuration parameters, wherein the configuration parameters are used to define the one or more second mobile reference signal bursts of each cell: Transmission cycle, The time offset relative to the synchronization signal block, Transmission bandwidth, The duration of the burst, and Frequency domain position.

12. The radio resource management measurement method according to claim 10, characterized in that: Also includes: Based on the received mobile reference signal, one or more of the following functions are performed: Demodulation, time synchronization tracking, frequency synchronization tracking or channel characteristic estimation of a physical broadcast channel in a synchronization signal block multiplexed with the one or more first mobile reference signal bursts.

13. The radio resource management measurement method according to claim 10, characterized in that: Also includes: The one or more first or second mobile reference signal bursts including a plurality of mobile reference signal symbols are received from a series of beams transmitted from the serving cell or one of the neighboring cells during a beam scanning process.

14. The radio resource management measurement method according to claim 13, characterized in that: A mobile reference signal sequence received from a beam is generated based on a beam index of the beam, such that the mobile reference signal sequence indicates the beam index of the beam.

15. The radio resource management measurement method according to claim 10, characterized in that: A mobile reference signal sequence is generated based on a cell identifier, a transmission reception point identifier and / or a transmission beam index of the serving cell or one of the neighboring cells.

16. The radio resource management measurement method according to claim 10, characterized in that: The frequency positions of the one or more first or second mobile reference signal bursts are determined based on a cell identifier, a transmission reception point identifier and / or a transmission beam index of the serving cell or one of the neighboring cells, wherein the serving cell or the one of the neighboring cells transmits the first or second mobile reference signal.

17. The radio resource management measurement method according to claim 10, characterized in that: Also includes: The mobile reference signal configuration is received via radio resource control signaling, broadcast or multicast system information, or a combination of the radio resource control signaling and the broadcast or multicast system information.

18. The radio resource management measurement method according to claim 10, characterized in that: The burst length of the one or more first or second mobile reference signal bursts is greater than the burst length of the synchronization signal burst containing the synchronization signal block.

19. A radio resource management measurement method, comprising: A user equipment receives a mobile reference signal transmitted from a serving cell and a neighboring cell of the user equipment, wherein each of the mobile reference signals comprises one or more first mobile reference signal bursts and one or more second mobile reference signal bursts, wherein each of the one or more first mobile reference signal bursts is multiplexed with a synchronization signal block, and the one or more second mobile reference signal bursts are configured to be transmitted or not transmitted, wherein when the one or more second mobile reference signal bursts are configured to be transmitted, a transmission bandwidth of the one or more second mobile reference signal bursts is equal to or greater than a transmission bandwidth of the synchronization signal block, wherein the burst length of the first mobile reference signal burst is greater than the burst length of the synchronization signal burst including the synchronization signal block, wherein each of the mobile reference signals is generated based on a cell identifier, a transmission reception point identifier and / or a transmission beam index of each cell corresponding to the mobile reference signal; and Based on the received mobile reference signal, a radio resource management measurement result is generated.

20. The radio resource management measurement method according to claim 19, characterized in that: Also includes: Based on the received mobile reference signal, one or more of the following functions are performed: Demodulation, time synchronization tracking, frequency synchronization tracking or channel characteristic estimation of a physical broadcast channel in a synchronization signal block multiplexed with the one or more first mobile reference signal bursts.

21. A device for wireless communication, comprising: A processor, configured to execute the steps of the downlink mobile reference signal transmission or radio resource management measurement method according to any one of claims 1 to 20.

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